Question

which element would most likely have an electron affinity measuring closest to zero?
na
al
rb
ar

Explanation:

Electron affinity is the energy change when an electron is added to a neutral atom in the gaseous state. Noble - gases have very stable electron configurations with full outer shells. Adding an electron to a noble - gas would require energy input as it disrupts the stable configuration. Argon (Ar) is a noble - gas. Sodium (Na), aluminum (Al), and rubidium (Rb) are metals and are more likely to lose electrons rather than gain them easily, but they still have non - zero electron affinities. Argon has an electron affinity closest to zero due to its stable configuration.

Answer:

Ar